Sulphamates cyclic

Both compounds are soluble in water and are readily hydrolysed to sulphamic acid, HjN S03" andammonia the hydrogen atoms are in each case replaceable by metals to form salts. Many derivatives of sulphamide and cyclic derivatives of sulphimide are known. 

The chemically and radiochemically pure NCA 5-[18F]fluoromethyl- and 5-/ -[18F]fluo-roethyl-10,ll-dihydro-5/7-dibenzo[tf, d]cyclohepten-5, 10-imines 151 and 152 have been prepared for i.v. injection from [18F]fluoride by nucleophilic substitution at the cyclic sulphamates 153 and 154 (equation 96). The labelled products 151 and 152 have been evaluated for receptor binding in animals and in man189. MK801, 155, readily crosses the BBB in mammals and binds to a high affinity site on the TV-methyl-D-aspartate receptor190. 

Synthesis of 345 has been achieved (equation 221) by reaction of [18F]fluoride with the triflamide alcohol 342 or via the cyclic sulphamate 344. 

The kinetics of the electrochemical reduction of sulphamic acid giving sulphite ion and ammonium hydroxide have been studied polarographically in aqueous solution in the presence of various salts51. The electrodissolution of lead sulphide, prepared by fusion or by sintering in sulphamic acid, has been measured by cyclic voltammetric, potentiodynamic and potentiostatic methods52. 

Cyclic sulphamates 95 appear to have a role as substrates in 18F-radiochemistry. Nucleophilic substitution by 18F occurs readily and cleavage of the N—S bond by acid gives the [18F] fluoro analogues of MK 801 (96), Z = 18F (equation 5)114. MK 801... 

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